Apple is said to have yet another product in the pipeline with a Retina Display, and this time it's an iPhone with a really big screen, according to a report from Reuters.

Apple is purportedly already placing orders with suppliers for a 4.6-inch iPhone Retina Display, Reuters said today, citing a report in South Korea's Maeil Business Newspaper. The phone is due in the second quarter, according to the report.

If accurate, that would be Apple's third device with a Retina Display. The others include the just-released 9.7-inch iPad and the 3.5-inch iPhone 4S.

The 960x640-pixel Retina Display on the iPhone packs in 326 pixels per inch while the new iPad's 2,048x1,536-pixel screen squeezes in 264 pixels per inch.

A relatively massive--for a smartphone, that is--4.6-inch glass screen would be a big step for Apple from the 3.5-inch iPhone. A larger phone may also allow Apple to include updated chips such as the A5X. That chip's marquee feature is quad-core graphics.

"There have been persistent rumors that the next generation iPhone would
carry a larger 4-inch screen. And we are convinced that Apple had exactly such
designs in late prototype stages in China," said MacRumors.